What type of mordant is used in aluminum hematoxylin?

The correct choice is aluminum because aluminum hematoxylin utilizes aluminum ions as a mordant. A mordant is a substance that helps in fixing dyes onto tissues during the staining process in histopathology. In the case of aluminum hematoxylin, aluminum salts serve to enhance the binding of hematoxylin to nuclear components, particularly the DNA and acidic proteins in the nuclei of the cells.

This staining technique is widely used due to its ability to provide distinct nuclear detail. The aluminum ions in the mordant interact with the dye, creating a complex that helps the dye adhere to the tissue, resulting in clear and consistent staining of cellular structures. The specificity of aluminum as the mordant highlights the importance of chemical interactions in histological staining, emphasizing the role of the mordant in achieving optimal staining results.